162 Britain's Heritage of Science 



profession who previously would have had to pursue their 

 science in solitude. But when all is said, much valuable 

 work is still being done, and was to an even greater extent 

 being done last century, by men who can only spare their 

 leisure to the pursuit of science. The work of the most 

 prominent of them may be briefly summarized. 



Francis Baily (1774-1844), the third son of a banker. at 

 Newbury, may serve as an example of a man who, without 

 exceptional abilities, exerted a great and beneficial influence 

 on the science of his time by perseverance, organizing power, 

 and an unselfish devotion to its interests. After a long and 

 adventurous journey to America, on which he spent three 

 years of his early life, he engaged in commercial pursuits. 

 While he was earning a considerable fortune, he found time 

 to write an important work on the " Doctrine of Interest 

 and Annuities analytically investigated and expounded," and 

 a similar book on the " Doctrine of Life Annuities and 

 Assurances." Through an acquaintance with the chemist 

 Priestley, he had developed a taste for experimental enquiry, 

 and later he became interested in astronomy, to which 

 subject he devoted himself entirely after his retirement from 

 business in 1825. He was one of the founders of the Royal 

 Astronomical Society, and acted as its secretary during the 

 first three years of its existence. He did not himself observe, 

 but his critical and historical work proved to be of great 

 value. The publication of serviceable star catalogues, first 

 for the Astronomical Society and then for the British 

 Association, is mainly due to his zeal. His experimental 

 work included the investigation of the effects of air resistance 

 on the time of swing of a pendulum, and a repetition of the 

 Michell-Cavendish experiment on gravitational attraction. 



John Peter Gassiot (1797-1877), originally a wine 

 merchant, was the first who systematically studied the 

 luminosity observed when an electric discharge passes 

 through gases at low pressure. The glass tubes with metal 

 electrodes which he had constructed for the purpose soon 

 came into common use under the name of Geissler tubes. 

 Gassiot was not only a successful experimenter, but also 

 a benefactor who used his wealth in encouraging and pro- 

 moting science. His gift of 10,000 to the Royal Society, 



